2020/12/23 · 2.2. Animals, Diets, Sampling, and Sample Preparation For the experimental purpose, a total of 90 Lohmann Lite Brown laying hens of early (24 weeks, n = 30), intermediate (42 weeks, n = 30), and late age (74 weeks, n = 30) were maintained at a commercial farm located in Yeoncheon-gun, Gyeonggi-do, South Korea. . Laying hens of these age groups are